Vulnerability-Lookup

FKIE_CVE-2021-47123

Vulnerability from fkie_nvd - Published: 2024-03-15 21:15 - Updated: 2026-08-04 10:16

Severity

7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: io_uring: fix ltout double free on completion race Always remove linked timeout on io_link_timeout_fn() from the master request link list, otherwise we may get use-after-free when first io_link_timeout_fn() puts linked timeout in the fail path, and then will be found and put on master's free.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/1f64f5e903b9d1d157875721e02adadc9d6f0a5d	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/447c19f3b5074409c794b350b10306e1da1ef4ba	Patch
af854a3a-2127-422b-91ae-364da2661108	https://git.kernel.org/stable/c/1f64f5e903b9d1d157875721e02adadc9d6f0a5d	Patch
af854a3a-2127-422b-91ae-364da2661108	https://git.kernel.org/stable/c/447c19f3b5074409c794b350b10306e1da1ef4ba	Patch

Impacted products

	Vendor	Product	Version
	linux	linux_kernel	*
	linux	linux_kernel	5.13

JSON

To clipboard

{
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    {
      "affectedData": [
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          "product": "Linux",
          "programFiles": [
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      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring: fix ltout double free on completion race\n\nAlways remove linked timeout on io_link_timeout_fn() from the master\nrequest link list, otherwise we may get use-after-free when first\nio_link_timeout_fn() puts linked timeout in the fail path, and then\nwill be found and put on master\u0027s free."
    },
    {
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      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: io_uring: corrige la doble liberaci\u00f3n de ltout al finalizar la ejecuci\u00f3n. Elimina siempre el tiempo de espera vinculado en io_link_timeout_fn() de la lista de v\u00ednculos de solicitud maestra; de lo contrario, es posible que obtengamos use-after-free la primera vez que io_link_timeout_fn() coloca el tiempo de espera vinculado en la ruta de falla, y luego ser\u00e1 encontrado y puesto en master gratis."
    }
  ],
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  "lastModified": "2026-08-04T10:16:46.883",
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          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
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  "weaknesses": [
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}

CVE-2021-47123 (GCVE-0-2021-47123)

Vulnerability from cvelistv5 – Published: 2024-03-15 20:14 – Updated: 2026-08-05 08:46

Title

io_uring: fix ltout double free on completion race

Summary

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-09-10 15:55 UTC

Assigner

Linux mitre root Scorecard

References

2 references

URL	Tags
https://git.kernel.org/stable/c/1f64f5e903b9d1d15…
https://git.kernel.org/stable/c/447c19f3b5074409c…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 90cd7e424969d29aff653333b4dcb4e2e199d791 , < 1f64f5e903b9d1d157875721e02adadc9d6f0a5d (git) Affected: 90cd7e424969d29aff653333b4dcb4e2e199d791 , < 447c19f3b5074409c794b350b10306e1da1ef4ba (git)
Linux	Linux	Affected: 5.11 Unaffected: 0 , < 5.11 (semver) Unaffected: 5.12.10 , ≤ 5.12.* (semver) Unaffected: 5.13 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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FKIE_CVE-2021-47123

CVE-2021-47123 (GCVE-0-2021-47123)

Tags

Sightings

Nomenclature

Related by attack behaviour